Congratulations on your decision to save a furry life.
Have you watched or read the Dog Whisperer? Cesar Milan is very good at explaining about bringing a dog into the pack. I would recommend that you check him out. He does have a great website with good info too.
We have two pound puppies and it is AMAZING how well they play together. That way they are not lonely when we are not at home. Both are Lab/Hound mixes (about 70 pounds now) and both were adult when we adopted them. Heidi was over 2 and she has treat aggression that we have to work on. (Make sure you get a good read on your dog's temperament before you pick)
Sadie was a little over 1 and she had not been well socialized. (When you don't get a puppy, you take on whatever baggage the dog carries with it. The good news: they learn fast and they want to do the right thing. Praise works, and sometimes treats.)
I think that the right dog (or dogs) will speak to you and you will know. (At least that is the way it was for us)
How exciting. :!: :!: :!: :!: